Definition of "lineman"

In the event of a failure, by the operation of a switch signalmen at the panel boxes can set up flashing white lights on certain signalling apparatus cases spaced at approximately half-mile intervals alongside the line, in order to call the lineman. The lineman can communicate with the signalman by plugging in a hand telephone at any one of these points.

1962 August, G. M. Kichenside, “Resignalling for the Kent Coast electrification—Phase II”, in Modern Railways, page 126

[…] or even, daring, spent the night up some pole in a lineman's tent like caterpillars, swung among a web of telephone wires, living in the very copper rigging and secular miracle of communication, untroubled by the dumb voltages flickering their miles, the night long, in the thousands of unheard messages.

1966, Thomas Pynchon, chapter 6, in The Crying of Lot 49, New York: Bantam Books, published 1976, page 135